\documentclass{tufte-book}

\usepackage{tikz}
\usepackage[super]{nth}
% \usepackage{parskip}
\usepackage{listings}

\usetikzlibrary{shapes,arrows}

\tikzstyle{decision} = [diamond, draw, fill=blue!20, 
    text width=4.5em, text badly centered, node distance=3cm, inner sep=0pt]
\tikzstyle{block} = [rectangle, draw, fill=blue!20, 
    text width=5em, text centered, rounded corners, minimum height=4em]
\tikzstyle{line} = [draw, -latex']
\tikzstyle{cloud} = [draw, ellipse,fill=red!20, node distance=3cm,
    minimum height=2em]

\titleformat{\section}{\scshape\Large}{\thesection}{1em}{}

\newenvironment{logEntry}[2]{ % Date, heading
  \noindent\textbf{#2}\marginnote{#1}\par}{\vspace{0.5cm}
}

\def\?#1{}

\newcommand{\writetitle}{0}
\newcommand{\mytitle}[2]{
  \ifthenelse{\writetitle=1}{\normalfont{#2:} \textbf{#1}}{}
}

\newcommand{\co}{Computer Organisation}
\newcommand{\gp}{General Psychology}
\newcommand{\da}{Digital Art: Photoshop}
\newcommand{\dd}{Documentation Development}

\newread\mysource

\begin{document}